Generally, in-cell touch panels utilize mutual capacitance principle to detect touch position of a finger. A pattern of touch electrodes is generally embedded within the touch panel. In order to avoid mutual interference between touch signals applied by touch electrodes and normal display signals in the touch screen, the touch function and the display function are typically driven in a time-division manner. As illustrated in FIG. 1, a frame period (Vsync) is divided into a touch interval (Touch) and a display interval (Display). Data signals and gate lines Gn-2, Gn-1, Gn, G3, G2 and G1 only work in the display interval, and touch signals only work in the touch interval. Thus, durations assigned for the touch interval and the display interval in each frame are relatively short, and deficiency of time caused by the time-division driving may result in various display and touch problems.